parse.com上的搜索功能将搜索结果覆盖在原始tableview上

Question

I'm pretty new at this and having a go using Parse.com as the backend server. I'm building a database of vegetables, and want to perform a search on the list pulled from parse.com. I have it all working, except for one annoying thing...

Now, I'm using storyboards and have created a custom cell which includes a PFImage thumbnail view, a label showing the vegetable, and then another label showing the season for the vegetable.

When the viewcontroller is called, the list populates perfectly and lists the vegetables in alphabetical order. Then I drag the window down to reveal the search bar. I begin typing in a vegetable name, and as I do so the original table data rows begin disappearing (as they should), but the problem is the original table data sticks around. So, for instance, I'll type "carrot", and all the rows disappear except the top row which still holds a thumbnail of an artichoke (and the label "Artichoke" as well). But overlayed on that row is also the word "Carrots", which is another vegetable in the list. If I tap on it, it properly seques to my detail view controller showing carrots. So everything is working properly, but I can't figure out how to make it so the search results aren't being written over the top of the original data.

Here's the code portions:

- (void)viewDidLoad
{

    self.tableView.backgroundColor = [UIColor clearColor];
    self.tableView.backgroundView=[[UIImageView alloc] initWithImage:
                                   [UIImage imageNamed:@"bg.jpg"]];

    [super viewDidLoad];

    //add the search bar
    self.searchBar = [[UISearchBar alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, 44)];
    self.tableView.tableHeaderView = self.searchBar;
    self.searchController = [[UISearchDisplayController alloc] initWithSearchBar:self.searchBar contentsController:self];
    self.searchController.searchResultsDataSource = self;
    self.searchController.searchResultsDelegate = self;
    self.searchController.delegate = self;
    CGPoint offset = CGPointMake(0, self.searchBar.frame.size.height);
    self.tableView.contentOffset = offset;
    self.searchResults = [NSMutableArray array];
    //done adding search bar
}

- (PFQuery *)queryForTable
{
    PFQuery *query = [PFQuery queryWithClassName:self.parseClassName];

    // If no objects are loaded in memory, we look to the cache first to fill the table
    // and then subsequently do a query against the network.
    /*    if ([self.objects count] == 0) {
     query.cachePolicy = kPFCachePolicyCacheThenNetwork;
     }*/

    [query orderByAscending:@"vegetable"];

    return query;
}

// Override to customize the look of a cell representing an object. The default is to display
// a UITableViewCellStyleDefault style cell with the label being the first key in the object.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath object:(PFObject *)object
{

    static NSString *simpleTableIdentifier = @"VegetableCell";

    UITableViewCell *cell = [self.tableView dequeueReusableCellWithIdentifier:simpleTableIdentifier];
    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:simpleTableIdentifier];
    }

    // more search stuff

    if (tableView == self.tableView) {
        cell.backgroundColor = cell.backgroundColor;

    }

    else if(tableView == self.searchDisplayController.searchResultsTableView) {

        PFObject *searchedVeggie = [self.searchResults objectAtIndex:indexPath.row];
        cell.textLabel.text = [searchedVeggie objectForKey:@"vegetable"];
        cell.backgroundColor = [UIColor whiteColor];
        tableView.rowHeight = self.tableView.rowHeight;
    }


    PFFile *thumbnail = [object objectForKey:@"vegetableImageFile"];
    PFImageView *thumbnailImageView = (PFImageView*)[cell viewWithTag:100];
    thumbnailImageView.image = [UIImage imageNamed:@"placeholder.jpg"];
    thumbnailImageView.file = thumbnail;
    [thumbnailImageView loadInBackground];

    UILabel *vegetableName = (UILabel*) [cell viewWithTag:101];
    vegetableName.text = [object objectForKey:@"vegetable"];

    UILabel *vegetableSeason = (UILabel*) [cell viewWithTag:102];
    vegetableSeason.text = [object objectForKey:@"vegetableSeason"];
    return cell;

}

Lower in the code is my prepareForSeque code and other search methods. I know it's a little ugly with repeated code, but I've been trying all sorts of things to fix my issue and wasn't going to get around to cleaning things up until I figured out the issue. Also, I created a new column on parse.com's data browser called lowerCaseVegetable since the search is case sensitive. So the search is actually performed on that column, but is displayed using the normal "vegetable" column, which has the vegetable name capitalized.

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    if ([segue.identifier isEqualToString:@"showVegetableDetail"]) {

        if (self.searchDisplayController.active) {
            NSLog(@"Search Display Controller");
            VeggieDetailViewController *destViewController = segue.destinationViewController;

            PFObject *object = [self.searchResults objectAtIndex: self.searchDisplayController.searchResultsTableView.indexPathForSelectedRow.row];
            Vegetables *vegetables = [[Vegetables alloc] init];
            vegetables.vegetable = [object objectForKey:@"vegetable"];
            vegetables.vegetableInfo = [object objectForKey:@"vegetableInfo"];
            vegetables.vegetableImageFile = [object objectForKey:@"vegetableImageFile"];
            vegetables.vegetableSeason = [object objectForKey:@"vegetableSeason"];
            destViewController.vegetables = vegetables;

        } else {
            NSLog(@"Default Display Controller");

        NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow];
        VeggieDetailViewController *destViewController = segue.destinationViewController;

        PFObject *object = [self.objects objectAtIndex:indexPath.row];
        Vegetables *vegetables = [[Vegetables alloc] init];
        vegetables.vegetable = [object objectForKey:@"vegetable"];
        vegetables.vegetableInfo = [object objectForKey:@"vegetableInfo"];
        vegetables.vegetableImageFile = [object objectForKey:@"vegetableImageFile"];
        vegetables.vegetableSeason = [object objectForKey:@"vegetableSeason"];
        destViewController.vegetables = vegetables;
        }
    }
}

// other search stuff

-(void)filterResults:(NSString *)searchTerm {

    [self.searchResults removeAllObjects];
    PFQuery *query = [PFQuery queryWithClassName: @"Vegetables"];
    [query whereKeyExists:@"lowerCaseVegetable"];
    [query whereKey:@"lowerCaseVegetable" containsString:searchTerm];
    NSArray *results = [query findObjects];
    [self.searchResults addObjectsFromArray:results];
}

-(BOOL)searchDisplayController:(UISearchDisplayController *)controller shouldReloadTableForSearchString:(NSString *)searchString {
    [self filterResults:searchString];
    return YES;
}

-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    if (tableView == self.tableView) {
        return self.objects.count;
    } else {
        return self.searchResults.count;
    }
}

-(void)callbackLoadObjectsFromParse:(NSArray *)result error:(NSError *)error {
    if (!error) {
        [self.searchResults removeAllObjects];
        [self.searchResults addObjectsFromArray:result];
        [self.searchDisplayController.searchResultsTableView reloadData];
    } else {
//        NSLog(@”Error: %@ %@”, [error userInfo]);
    }
}

I have a feeling I'm just making a stupid newbie mistake here, but I've only been at this since May, and specifically fighting this issue the last two weeks. I figured it was about time to ask for help.

Answer 1

I just implemented search in my parse app and I think I see the problem:

In your filterResults method try using findObjectsInBackgroundWithBlock instead of findObjects like this:

[query findObjectsInBackgroundWithBlock:^(NSArray *array, NSError *error){

         [self.searchResults addObjectsFromArray:array];
        [self.searchDisplayController.searchResultsTableView reloadData];

    }];

prepareForSegue:

Vegetables *vegetables = [[Vegetables alloc] init];
   vegetables.vegetable = [self.selectedObject objectForKey:@"vegetable"];
   vegetables.vegetableInfo = [self.selectedObject objectForKey:@"vegetableInfo"];
   vegetables.vegetableImageFile = [self.selectedObject objectForKey:@"vegetableImageFile"];
   vegetables.vegetableSeason = [self.selectedObject objectForKey:@"vegetableSeason"];
   destViewController.vegetables = vegetables;